<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>math 对象</title>
	<script type="text/javascript">
		
		var a = 10;
		var b = 20;

		var arr = [];

		

		for(var i=0;i<20;i++){

			var num = Math.floor(Math.random()*(b-a+1)+a);

			arr.push(num);

		}


		alert(arr);









	</script>
</head>
<body>
	
</body>
</html>